<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>匿名函数-函数表达式</title>
</head>

<body>
  <script>
    // 匿名函数 - 函数表达式
     let fn=function(){
      // web Api会用到
      // 函数体
      document.write('aaa')
     }
     fn()

  </script>
</body>

</html>